Room‐Temperature Syntheses of Methyl Ethyl Carbonate Using an Amino‐Functionalized Ionic Liquid Catalyst

This study reports the development of a novel amino‐functionalized ionic liquid catalyst, namely 1‐butyl‐3‐methylimidazolium amino triazole ([EMIM]ATZ), for the efficient and sustainable synthesis of ethyl methyl carbonate (EMC) via transesterification of dimethyl carbonate (DMC) and ethanol (C 2 H 5 OH) at room temperature. Addressing the limitations of conventional catalytic systems that require elevated temperatures (> 75°C), [EMIM]ATZ achieves 62% DMC conversion and 56% EMC yield within 8 h under room temperature (25°C), while conventional ionic liquids ([EMIM]Cl, [EMIM]BF 4 , [EMIM]PF 6 etc.) showed almost no activity at room temperature. The catalyst's superior activity stems from its strong basicity (pH ≈ 9.2) and enhanced CO 2 absorption capacity (200 mg·g −1 ), which synergistically activate C 2 H 5 OH and stabilize reaction intermediates. Structural characterization via FTIR and thermogravimetric analysis (TGA) confirmed the catalyst's thermal stability and recyclability, with no significant degradation observed over five reuse cycles (89% activity retention). In addition, the ionic liquid was also able to catalyze the synthesis of methyl propyl carbonate (PMC) and methyl butyl carbonate (BMC) at room temperature.